fix: issues with empty tool calls and handling excessively long tool results

agent/protocol/agent_stream.py

@@ -350,6 +350,15 @@ class AgentStreamExecutor:
                             # Fallback to full JSON
                             result_content = json.dumps(result, ensure_ascii=False)
 
+                        # Truncate large tool results to prevent message bloat
+                        # Keep tool results under 50KB to avoid context window issues
+                        MAX_TOOL_RESULT_CHARS = 20000
+                        if len(result_content) > MAX_TOOL_RESULT_CHARS:
+                            truncated_len = len(result_content)
+                            result_content = result_content[:MAX_TOOL_RESULT_CHARS] + \
+                                f"\n\n[Output truncated: {truncated_len} chars total, showing first {MAX_TOOL_RESULT_CHARS} chars]"
+                            logger.info(f"📎 Truncated tool result for '{tool_call['name']}': {truncated_len} -> {MAX_TOOL_RESULT_CHARS} chars")
+
                         tool_result_block = {
                             "type": "tool_result",
                             "tool_use_id": tool_call["id"],
@@ -678,6 +687,14 @@ class AgentStreamExecutor:
         tool_calls = []
         for idx in sorted(tool_calls_buffer.keys()):
             tc = tool_calls_buffer[idx]
+
+            # Ensure tool call has a valid ID (some providers return empty/None IDs)
+            tool_id = tc.get("id") or ""
+            if not tool_id:
+                import uuid
+                tool_id = f"call_{uuid.uuid4().hex[:24]}"
+                logger.debug(f"⚠️ Tool call missing ID for '{tc.get('name')}', generated fallback: {tool_id}")
+
             try:
                 # Safely get arguments, handle None case
                 args_str = tc.get("arguments") or ""
@@ -694,7 +711,7 @@ class AgentStreamExecutor:
                 # Return a clear error message to the LLM instead of empty dict
                 # This helps the LLM understand what went wrong
                 tool_calls.append({
-                    "id": tc["id"],
+                    "id": tool_id,
                     "name": tc["name"],
                     "arguments": {},
                     "_parse_error": f"Invalid JSON in tool arguments: {args_preview}... Error: {str(e)}. Tip: For large content, consider splitting into smaller chunks or using a different approach."
@@ -702,7 +719,7 @@ class AgentStreamExecutor:
                 continue
 
             tool_calls.append({
-                "id": tc["id"],
+                "id": tool_id,
                 "name": tc["name"],
                 "arguments": arguments
             })

models/linkai/link_ai_bot.py

@@ -628,10 +628,29 @@ def _handle_linkai_stream_response(self, base_url, headers, body):
                         break
                     try:
                         chunk = json.loads(line)
-                        yield chunk
                     except json.JSONDecodeError:
                         continue
 
+                    # Check for error responses within the stream
+                    # Some providers (e.g., MiniMax via LinkAI) return errors as:
+                    # {'type': 'error', 'error': {'type': '...', 'message': '...', 'http_code': '400'}}
+                    if chunk.get("type") == "error" or (
+                        isinstance(chunk.get("error"), dict) and "message" in chunk.get("error", {})
+                    ):
+                        error_data = chunk.get("error", {})
+                        error_msg = error_data.get("message", "Unknown error") if isinstance(error_data, dict) else str(error_data)
+                        http_code = error_data.get("http_code", "") if isinstance(error_data, dict) else ""
+                        status_code = int(http_code) if http_code and str(http_code).isdigit() else 400
+                        logger.error(f"[LinkAI] stream error: {error_msg} (http_code={http_code})")
+                        yield {
+                            "error": True,
+                            "message": error_msg,
+                            "status_code": status_code
+                        }
+                        return
+
+                    yield chunk
+                        
     except Exception as e:
         logger.error(f"[LinkAI] stream response error: {e}")
         yield {

models/minimax/minimax_bot.py

@@ -285,10 +285,16 @@ class MinimaxBot(Bot):
                                 text_parts.append(block.get("text", ""))
                             elif block.get("type") == "tool_result":
                                 # Tool result should be a separate message with role="tool"
+                                tool_call_id = block.get("tool_use_id") or ""
+                                if not tool_call_id:
+                                    logger.warning(f"[MINIMAX] tool_result missing tool_use_id")
+                                result_content = block.get("content", "")
+                                if not isinstance(result_content, str):
+                                    result_content = json.dumps(result_content, ensure_ascii=False)
                                 tool_results.append({
                                     "role": "tool",
-                                    "tool_call_id": block.get("tool_use_id"),
-                                    "content": str(block.get("content", ""))
+                                    "tool_call_id": tool_call_id,
+                                    "content": result_content
                                 })
 
                     if text_parts:

models/openai_compatible_bot.py

@@ -242,10 +242,17 @@ class OpenAICompatibleBot:
 
                     # First, add tool result messages (must come immediately after assistant with tool_calls)
                     for block in tool_results:
+                        tool_call_id = block.get("tool_use_id") or ""
+                        if not tool_call_id:
+                            logger.warning(f"[OpenAICompatible] tool_result missing tool_use_id, using empty string")
+                        # Ensure content is a string (some providers require string content)
+                        result_content = block.get("content", "")
+                        if not isinstance(result_content, str):
+                            result_content = json.dumps(result_content, ensure_ascii=False)
                         openai_messages.append({
                             "role": "tool",
-                            "tool_call_id": block.get("tool_use_id"),
-                            "content": block.get("content", "")
+                            "tool_call_id": tool_call_id,
+                            "content": result_content
                         })
 
                     # Then, add text content as a separate user message if present
@@ -265,8 +272,11 @@ class OpenAICompatibleBot:
                         if block.get("type") == "text":
                             text_parts.append(block.get("text", ""))
                         elif block.get("type") == "tool_use":
+                            tool_id = block.get("id") or ""
+                            if not tool_id:
+                                logger.warning(f"[OpenAICompatible] tool_use missing id for '{block.get('name')}'")
                             tool_calls.append({
-                                "id": block.get("id"),
+                                "id": tool_id,
                                 "type": "function",
                                 "function": {
                                     "name": block.get("name"),